Bridge near Limyra
Bridge near Limyra | |
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![]() The 4th arch, today half-buried. The exceptionally flat profile of the arch is evident. | |
Coordinates | 36°20′56″N30°12′23″E/ 36.34887°N 30.20651°E |
Carries | Pedestrian and pack animal traffic |
Crosses | Alakır Çayı |
Locale | Limyra,Lycia,Turkey |
Official name | Kırkgöz Kemeri |
Heritage status | None |
Characteristics | |
Design | Segmentalarch bridge |
Material | Brick,stonemasonryandrubble |
Total length | 360 m (1,181.1 ft) |
Width | 3.55–4.30 m (11.6–14.1 ft) |
Longest span | 14.97 m (49.1 ft) |
No.of spans | 28 (once 27) |
Piers in water | Today approx. 5 |
Load limit | 30 t + 500kp/m² |
History | |
Construction end | Presumably 3rd century AD |
Location | |
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![](https://upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/30px-Commons-logo.svg.png)
TheBridge near Limyra(inTurkish:Kırkgöz Kemeri,"Bridge of the Forty Arches" ) is a lateRoman bridgeinLycia,in modern south-westTurkey,and one of the oldestsegmentedarch bridgesin the world. Located near the ancient city ofLimyra,it is the largest civil engineering structure ofantiquityin the region, spanning the Alakır Çayı river over a length of 360 m (1,181.1 ft) on 26 segmental arches. These arches, with a span-to-rise ratio of 5.3:1, give the bridge an unusually flat profile, and were unsurpassed as an architectural achievement until the lateMiddle Ages.Today, the structure is largely buried by river sediments and surrounded bygreenhouses.Despite its unique features, the bridge remains relatively unknown, and only in the 1970s did researchers from theIstanbulbranch of theGerman Archaeological Institutecarry outfield examinationson the site.
Field examinations
[edit]![](https://upload.wikimedia.org/wikipedia/commons/thumb/e/e5/Bridge_near_Limyra._Pic_11.jpg/220px-Bridge_near_Limyra._Pic_11.jpg)
No information on the bridge survives fromancientsources. The first descriptions appear in European travellers' accounts from the 19th century. The British archaeologistCharles Fellowswas the first to explore the region of Lycia, and visited the bridge in May 1840. Fellows, as well as T.A.B. Spratt and Edward Forbes, who visited the site two years later, describe it as having 25 arches.[1]In 1882, an Austrian expedition, includingOtto Benndorf,interpreted the structure as part of anancient roadthat connected Limyra with the city of Attaleia (modernAntalya) to the east. However, this mission failed to produce any plans or sketches of the site.[1]
The first, and as of 2008[update]only scientific examination of the bridge was undertaken by the German archaeologists Wolfgang W. Wurster and Joachim Ganzert in two successive days in September 1973, and completed through further visits in subsequent years.[1]Their findings were published in 1978 in theArchäologischer Anzeigerjournal of theGerman Archaeological Institute,with the express intent of bringing the imperiled state of the hitherto almost intact bridge into the spotlight:[2]
Recently, citrus fruit plantations were created in this fertile bottomland; greenhouses for early vegetables are now being built east of the bridge. The bridge is greatly endangered through the beginning of intensive cultivation in the vicinity. The locals strip the still intact bridge surface for stones; bulldozers employed to build irrigation canals rip the structure apart and crush the stone pavement with theircaterpillar tracks.
In 1993, the civil engineer Colin O'Connor summarized their report in his English-languagemonographon Roman bridges, and also emphasized the exceptional character of this bridge.[3]No further scientific examinations of the Limyra Bridge are known.
Location and situation
[edit]![](https://upload.wikimedia.org/wikipedia/commons/thumb/5/53/Bridge_near_Limyra._Pic_01.jpg/220px-Bridge_near_Limyra._Pic_01.jpg)
The bridge crosses the Alakır Çayı stream, whose ancient name is unknown, 3.2 km (2.0 mi) east of the ruins of Limyra (distance measured from the city's theatre) and 3.8 km (2.4 mi) north of the modern coastline, close to the modern road fromTurunçovatoKumluca.[1]The local topography is dominated by the foothills of theToçak Dağımountains, which blend here with the alluvial bottomlands of the Bay ofFinike.[1]In this transitional area, the bridge was built immediately above the point where the narrow river valley opens into the wide estuary plain, and where the crossing of the river during the rain period would be obstructed by high water.[4]While the eastern end of the bridge levels off at the gravel plain, the western end abuts directly to the rising rock wall of the mountain, presumably for protection against floods.[5]The resulting sharp bend in the course of the road could also be exploited in case of need to block the road. A modern dam, Alakır Barajı, was constructed upstream for irrigation purposes and flood protection.[5]
Lycia did not, in contrast to otherRoman provinces,possess a very developed road system. While the north–south traffic was conducted primarily through the few river valleys, the east–west routes led, unlike today, mostly on and along the mountain ridges.[6]This particular road, leading from Limyra over the Alakır Çayı and into the neighbouring region ofPamphyliaand Attaleia, must have been of special importance, since the two regions were united in a single province,Lycia et Pamphylia,until the 4th century. In comparison to the main arterial roads of the Roman Empire however, the roads of Lycia were, with 3–4 m (9.8–13.1 ft) width, rather modest and confined to pedestrian and pack animal traffic.[6]This is further corroborated by the fact that no wagon ruts are evident on the paving of the Limyra bridge, nor any traces of a parapet or breastwork.[7]
Construction
[edit]![](https://upload.wikimedia.org/wikipedia/commons/thumb/a/ab/Bridge_near_Limyra._Pic_02.jpg/220px-Bridge_near_Limyra._Pic_02.jpg)
With a length of 360 m (1,181.1 ft), the Limyra Bridge qualifies as the largest surviving engineering achievement of antiquity in Lycia.[8]The bridge stands on 26 uniform segmental arches consisting of a double, radially laid course of bricks.[9]At the eastern end, the original 27th arch has been replaced by two smaller, semicircular arches of later construction. The latter are built with a single course of bricks. Traces of the original, flat beginning of the collapsed arch are still visible on the piers.[9]
At the time of Wurster's and Ganzert's visit to the site, the entire bridge was buried by river sediments up to thespringing lineof the vaults. No efforts to dig them up were undertaken by Wurster and Ganzert.[5]Only two of the 28 arches were exposed enough so that direct measurements of theclear spanand the pier width could be undertaken. It was, however, possible to calculate the dimensions of the remainingbaysfrom their exposed sections.[10]
Architecture
[edit]Arches and piers
[edit]![](https://upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Limyra_Bridge_Arch.svg/300px-Limyra_Bridge_Arch.svg.png)
The spans of the arches ranged from 11.60 m (38.1 ft) to 14.97 m (49.1 ft) (arches 2 and 26 respectively).[9]Based on the size of the spans, one can distinguish four groups, with the followingmedianvalues:[9]
- 11.60–12.30 m (38.1–40.4 ft) for four arches (Nos. 2, 3, 7, 21)
- 12.75 m (41.8 ft) for fourteen arches (Nos. 5, 9–15, 17–19, 22–24)
- 13.10 m (43.0 ft) for four arches (Nos. 1, 4, 6, 8)
- 13.60 m (44.6 ft) for three arches (Nos. 16, 20, 25)
The reason for this grouping is unclear; they certainly cannot be attributed to an attempt to match the lay of the river bed. The differences however could point to the repeated use of differently-sizedfalseworkstructures in the construction of thebarrel vaults(see animation below).[11]
Only in a single case, between arches 26 and 27, were Wurster and Ganzert able to determine the breadth of a pier: 2.10 m (6.9 ft). Subtracting this value from the common arch span of 12.75 m (41.8 ft), aclear spanof 10.65 m (34.9 ft) remains.[12]Since all arches have a rise of ca. 2 m (6.6 ft), the Limyra Bridge has an unusually large span-to-rise ratio of5.3 to 1.Such flattened arches were very rare at the time for stone bridges, and were not matched and surpassed until the reappearance of segmental arch bridges in 14th centuryItaly.For the largest arch in the Limyra Bridge, the ratio is even greater, spanning a width 6.4 times its height.[12]The two later arches, in contrast, are, with a ratio of 2.7:1, quite ordinary semi-circular arches.[12]
Height
[edit]![](https://upload.wikimedia.org/wikipedia/commons/thumb/8/83/Bridge_near_Limyra._Pic_08.jpg/220px-Bridge_near_Limyra._Pic_08.jpg)
The total height of the bridge could not be determined because most of the structure is silted up. However, the distance between the arches' abutments and the pavement surface could be determined at only 3.25 m (10.7 ft).[13]
The surface level is almost horizontal: the roadway lies at a height of 20.05–20.55 m (65.8–67.4 ft) abovesea levelbetween arches 1 to 20, and falls slightly in its eastern section, between arches 21 and 26 to a level of 19.94 to 19.66 m (65.4 to 64.5 ft).[14]Since there is no indication of a later sinking of the structure, this nearly uniform height indicates careful levelling and the existence of solid pier foundations.[15]In contrast, the lengthwise axis of the bridge displays often significant deviations from arch to arch.[15]
Statics
[edit]Remarkably, the support line of the structure'sdead loadis almost identical with the curve of the vault arch.[16]Thestatical analysisof the bridge proves the structure's great load capacity:
In modern classification, the bridge would be able to support loads of aClass 30 bridge(perDIN 1072); this would mean, that it could support a 30-tonnevehicle on one arch and additionally on the remaining surface of the arch a load of 500kp/m².The bridge was thus very safe for ancient traffic.[17]
Materials
[edit]The Limyra bridge was built in a composite manner ofbrick,stonemasonry,andrubble.
Arches
[edit]![](https://upload.wikimedia.org/wikipedia/commons/thumb/c/c5/Bridge_near_Limyra._Pic_09.jpg/220px-Bridge_near_Limyra._Pic_09.jpg)
The bricks of the segmental arches are made of yellow-red clay, mixed with fine brick fragments. The bricks are rectangular plates, measuring ca. 40 cm × 50 cm (15.7 in × 19.7 in) and 5 cm (2.0 in) thick. They are placed with the shorter side upright facing outwards, so that the total thickness of the arches measuresca. 80 cm.[12]The bricks are bound withgroutof lime mortar mixed with brick shards and fine gravel, forming 4 cm (1.6 in)-thickjoints.The two later semi-circular arches were built with smaller bricks, although surviving bricks from the original arch were re-used at places.[12]The abutment stones are dressed limestoneashlarblocks, and form a sloping surface to support the arches.
The double-layer technique facilitated a more effective use of the falsework, since they could be removed and used elsewhere as soon as the lower course was finished:
The construction of the two layers of the double brick-arches in two separate phases had two advantages. In the first phase, the falsework only had to carry the weight of the lower course, so that it could itself be of lighter construction. In the second phase, the weight of the upper layer could be already borne by the lower vault; the falsework was thus already available for use in a different arch.[17]
![](https://upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Limyra_Bridge_Workflow.gif/500px-Limyra_Bridge_Workflow.gif)
![](https://upload.wikimedia.org/wikipedia/commons/thumb/3/31/Bridge_near_Limyra._Pic_12.jpg/220px-Bridge_near_Limyra._Pic_12.jpg)
Superstructure
[edit]As far as can be determined, between arches 2 to 21, the outer facing of thesuperstructureconsists of four layers of brick, followed by layers of rough stonemasonry bound with mortar.[18]In contrast, between arches 22 and 26, as well as in both ramps on either end, the facing consists of ashlar blocks.[7]The two repaired arches 27a and 27b are differentiated from the earlier work through the use of smaller unworked stones and the incorporation of irregularly placed brick tiles.[7]In arch 26, the lower side of the arch still features a projecting bearing used for the placement of the falsework.[18]
The interior of the superstructure consists of a combination of unworked masonry blocks and large river boulders, bound with lime mortar.[18]
Pavement
[edit]The bridge surface is located only 30–40 cm (11.8–15.7 in) over the arches' apex, is 3.55–3.70 m (11.6–12.1 ft) wide, increasing towards either end at 4.30 m (14.1 ft) and projects ca. 10 cm (3.9 in) over the superstructure on either side.[7]It is paved with large and irregular limestonecobblestones,although smaller pebbles have been used in the repairs at the two semicircular arches.[7]
Dating
[edit]The exact chronological placement of the Limyra bridge is difficult due to its unique place withinRoman engineeringtradition and the lack of comparable structures.[17]Wurster and Ganzert used following characteristics as a starting point:[19]
- multiple arches of same width, and horizontal deck level with only small-gradient ramps on either end
- very flat segmental arches built with double, radially layered brick courses
- the use of mortar in the stonework
- exterior facing primarily rough masonry with interspersed bricks, partly dressed ashlar blocks
- exceptionally large paving stones.
In contrast to these, most Roman stone bridges were faced with ashlar and rested onvoussoirarches,[20]a method which is dominant in other vaulted structures in Lycia too.[21]Compared to the massive and tall semicircular-arched bridges that are typical ofRoman architecture,the Limyra bridge, with its flat segmented arches, offers a markedly lower and more elongated appearance,[22]so that Wurster and Ganzert offer a "provisional" late dating, approximately during the reign of emperorJustinian Iin the 6th century, during which the use of mixed brick and stone is attested in other structures of the region.[23]
On the other hand, this mixed technique is already present in the 3rd-century ADaqueductofAspendos,and the Romans certainly knew how to build segmented-arched bridges, as attested by surviving examples, three of which are listed by Wurster and Ganzert themselves.[24]An earlier construction date in the 2nd or3rd centuries ADcannot therefore be excluded.[25]The case for an earlier construction date has been strengthened in recent years with the discovery of further seven Roman segmented arch bridges.[26]The remnants of the nearbyKemer Bridgeover the riverXanthos,which dates to the 3rd century and has some architectural similarities with the Limyra bridge, could further reinforce that case.[27]
See also
[edit]References
[edit]- ^abcdeWurster & Ganzert 1978,p. 288
- ^Wurster & Ganzert 1978,pp. 289–290
- ^O’Connor 1993,p. 126:
Wurster and Ganzert describe the remarkable bridge near Limyra… The outstanding feature of the bridge is that the arches are segmental… It is believed that the bridge isRoman.If this is the case, then it is one of the few truly segmental Roman stone arch bridges,…
- ^Wurster & Ganzert 1978,pp. 288f.
- ^abcWurster & Ganzert 1978,p. 289
- ^abWurster & Ganzert 1978,p. 303
- ^abcdeWurster & Ganzert 1978,p. 295
- ^Wurster & Ganzert 1978,pp. 288, 291
- ^abcdWurster & Ganzert 1978,p. 291
- ^Wurster & Ganzert 1978,p. 290
- ^Wurster & Ganzert 1978,pp. 291f.
- ^abcdeWurster & Ganzert 1978,p. 292
- ^Wurster & Ganzert 1978,pp. 292, fig. 5, 295
- ^Wurster & Ganzert 1978,pp. 295f.
- ^abWurster & Ganzert 1978,p. 296
- ^Wurster & Ganzert 1978,p. 297
- ^abcWurster & Ganzert 1978,p. 299
- ^abcWurster & Ganzert 1978,p. 293
- ^Wurster & Ganzert 1978,pp. 299ff.
- ^Wurster & Ganzert 1978,p. 301
- ^Wurster & Ganzert 1978,p. 300, note 10
- ^Wurster & Ganzert 1978,pp. 301ff.
- ^Wurster & Ganzert 1978,p. 302
- ^Wurster & Ganzert 1978,pp. 302–307
- ^Wurster & Ganzert 1978,p. 300
- ^O’Connor 1993,p. 171
- ^Wurster & Ganzert 1978,pp. 304–307
Sources
[edit]- O’Connor, Colin (1993),Roman Bridges,Cambridge University Press, pp. 126 (E23),ISBN0-521-39326-4
- Wurster, Wolfgang W.; Ganzert, Joachim (1978), "Eine Brücke bei Limyra in Lykien" [A bridge at Limyra in Lycia],Archäologischer Anzeiger(in German), Berlin:German Archaeological Institute,pp. 288–307,ISSN0003-8105
External links
[edit]Media related toBridge near Limyraat Wikimedia Commons
- Bridge near LimyraatStructurae
- "Bridge near Limyra".brueckenweb.de(in German).